Debugging Script in IE using Microsoft Script Debugger

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Debugging Script in IE using Microsoft Script
Debugger Visual Studio .NET 2005

• April 15, 2007

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Change IE setting to enable debug
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IE Debug Tools

• Microsoft Visual Studio .Net 2000/2003/2005
• Download Visual Web Developer 2005 free from
  http//msdn.microsoft.com/vstudio/express/download
  s/
• Microsoft Script Debugger
• Microsoft Script Editor
• installed with Office 2003
• Office 2007 has removed it.

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Get Microsoft Script Debugger

• http//www.microsoft.com/downloads/details.aspx?fa
  milyid2F465BE0-94FD-4569-B3C4-DFFDF19CCD99displa
  ylangen
• Advantage
• Light weight, scd10en.exe only 653kb
• Shortcoming
• Less functions than VS.NET

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Visual Studio .NET 2005

• To debug
• Client scripts
• Server scripts
• Allowing you to
• View the source code of the script you are
  debugging.
• Control the pace of script execution.
• View and change variable and property values.
• View and control script flow.

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Ways to trigger debugger

• Manually
• Attach to IE process
• From your browser
• View-gtScript Debugger-gtOpen
• View-gtScript Debugger-gtBreak at next statement
• Programmatically
• VBScript stop
• JavaScript debugger Suspends execution.
• By responding to a script error

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Debugging facilities

• Script Explorer Debug -gt Windows -gt Script
  Explorer
• Viewing source
• Set breakpoints
• Controlling program execution
• Step over, F10 Step into, F11 Step out,
• Viewing and controlling program flow
• Move up to down in the executing lines

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Debugging facilities

• Viewing and changing variable
• Autos
• displays variables used in the current statement
  and the previous statement
• Locals
• displays variables local to the current context.
• Watch

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Debugging Facilities

• Call Stack
• Breakpoints
• Command Window
• Execute Macro, such as Edit.Find
• Immediate Window
• Evaluate expression
• Ouput

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Get VS back when mixed up

• VS.NET debugger does not start, set in
  Tools-gtOptions, select Script

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How script debugging works

• For those who are curious about whats behind the
  debugger

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Active Script Debugging Overview
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Players in Debugging JavaScript

• Script host (example wscript.exe, mshtml.dll or
  asp.dll). This is the application that wants to
  run script.
• Script engine (jscript.dll/vbscript.dll). This is
  responsible for interpreting the stream of script
  statements.
• Process Debug Managed (pdm.dll). This is a dll
  written by the debugger team. It runs inside of
  the script process.
• DCOM interface into the process.
• Script Debug Engine.

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Wrap up

• You can debug JavaScript using MS Script
  Debugger or Visual Studio .NET.
• Keyword "debugger is used to trigger the
  debugger.
• Like many great software, Visual Studio .NET is a
  versatile tool.
• Enjoy!